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% ==========Title==========

\title{\bfseries 第四章作业 } 
\author{\bfseries 谈昊\quad2020E8013282037}

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\date{}
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\begin{document}
\maketitle


\paragraph{Answer}
\begin{itemize}
    \item[一、] 
    \begin{itemize}
        \item $$S_w=\left\{
            \begin{matrix}
                0.44444444 &-0.22222222 &-0.22222222 \\
                -0.22222222  &0.44444444 &-0.22222222 \\
                -0.22222222 &-0.22222222 & 0.44444444
            \end{matrix}\right\}
            $$
        \item $$S_b=\left\{
            \begin{matrix}
                0.7654321&  0.16049383  \\
                0.16049383& 0.7654321 
            \end{matrix}\right\}
            $$
    \end{itemize}
    
    
    \item[二、] 
    如下图：
        \begin{figure}[H]
            \centering
            \subfigure[2D]{
\includegraphics[width=0.45\textwidth]{KL_2D.png}
%\caption{fig1}
}
\subfigure[1D]{
\includegraphics[width=0.45\textwidth]{KL_1D.png}
%\caption{fig1}
}
        \end{figure}
\end{itemize}

\end{document}

